Most treatments of the American auger bit begin with the 1809 patent of Connecticut resident Ezra L'Hommedieu, who is said to have invented a double-twist auger in 1809. The idea is older; a British patent existed as early as 1770. Though documentation is scarce, the honor for the first manufacture of the double-twist screw auger in North America likely goes to William Henry and John Henry Rauch of Lancaster County, Pennsylvania, men who put a commercially viable product on the market in 1772.(1)
Job T. Pugh of Philadelphia is reported to have been making double-twist augers in 1774, but the evidence does not support the claim.(2) There are several other early claimants, among them John Washburn of Kingston, Massachusetts,(3) Thomas Snell of Ware, Massachusetts,(4) and the duo Nathan Palmer and Andrew Hartshorn of Mansfield, Connecticut.(5)
The bits seen here are of the common sizes used by a general-purpose worker. It's unlikely that any would have been used to bore holes in the timbers used to build a barn, frame a ship, or tap a maple tree. The bits in the box range from 6 to 10 1/2 inches in length, mere babies compared to the ten-foot augers used to bore the timbers for the gates of the locks of the first Panama Canal.
Some of the bits have a single spiral, while others have shanks that were flattened and twisted to form what is known as a double-twist bit. In either case, the function of the spiral was the same—to guide waste wood up the shank so that the bit would not have to be pulled from the hole and the chips cleared out to allow for further boring. None of the bits in the box feature the solid center stem popularized by the Irwin Auger Bit Company—not that the design is inherently less interesting—but because none happened to be on hand when the owner assembled the collection.
As interesting as a comprehensive history of the United States auger bit industry from its earliest days might be, Auger Bit Heaven was not created for that purpose. The site serves instead, as a venue to explore various aspects of auger bit manufacture that have caught the author's fancy.
Here are a few terms that will be helpful as you go through these histories:
Auger vs. Auger bit
The terms wood auger and auger bit refer to a tool for boring deep, clean holes in wood using a spiral design, often featuring a lead screw. When in use, traditional wood augers typically have a handle attached. The handle sits at a right angle to the shaft, with the result that they are often referred to as "T-augers." Auger bits are designed to be inserted into a chuck and are generally shorter than traditional wood augers. While auger bits are by definition augers, a wood auger is not necessarily an auger bit.
Double-Twist
Once referred to as a double-pod auger, a double-twist auger has two channels for moving chips up and away from the cutting head. It is traditionally formed by heating a piece of rod or bar stock, hammering part of it flat, and then twisting the flattened part of the stock to form a spiral. The honor for the first manufacture of the double twist screw auger in North America likely goes to William Henry and John Henry Rauch of Lancaster County, Pennsylvania, men who put a commercially viable product on the market in 1772.(6)
Single-Twist
Sometimes referred to as a single-spiral auger, a traditional single-twist auger has a hollow center. Originally formed by wrapping a heated bar around a mandrel, twisting machines soon took over the laborious task. The advantage of the single-twist auger is its ability to clear chips from a deep hole. Double-twist augers have a tendency to clog in this situation, forcing a worker to remove the auger from the hole to clear the chips. Ezra L'Hommedieu is credited with developing the single-twist auger in 1816. A single-twist auger is sometimes referred to as a single-spiral auger.

Solid-Center
A solid-center auger bit features a thick, solid steel core providing increased rigidity and stability while boring. Originally patented by George Shetter with a single cutter in 1829, the inventor improved on his design in 1831 by adding a second cutter. Fifty-three years later, in 1884, William Demitt patented an auger virtually identical to that of Shetter's 1829 invention, and in 1887, Charles E. Irwin patented a double-cutter almost identical to that patented by Shetter in 1831. The original Shetter augers were not widely distributed, with the result that the later mass-produced version of his invention became known as the Irwin pattern.(7)

Scotch lip
A Scotch lip auger typically features a pair of cutters with lips that project upward from the main cutting edges when the bit is held in the working position. The origins of the pattern have been lost to time, but the design is seen on American augers dating back to the latter decades of the 18th century.

Double-spur
The term "double-spur" can be confusing because it does not refer to an auger with two cutting spurs. Instead, it calls attention to a spur that protrudes both above and below the auger's main cutting edge or edges. Indeed, some bits were manufactured with a single double-spur. The development of the double-spur is not well documented. An early depiction of the double-spur appears in a patent drawing from 1831. The patent makes no claim for the originality of the spur.(8)

Extension Lip
The term "extension lip" refers to the specific design of the spurs that extends beyond the auger's main cutting edges. Originally found almost exclusively on double-twist bits, the design was widely adopted after the expiration of Jennings' Patent, appearing in various forms on single and double-twist augers as well as solid-center bits. The extension-lip auger bit was patented by Russell Jennings in 1854.(9)
